1. Field of the Invention
The present invention relates generally to glass window and window wall safety systems, and more particularly to an improved system for restraining glass within an opening using a glass covering membrane in combination with an apparatus for clamping the edges of the membrane to a frame circumscribing the windowed opening.
2. Description of the Prior Art
Window film has been applied for many years to glass windows for tinting and other purposes and, due to its tensile strength, has had the incidental function of adding safety to the window in that it is difficult to tear and usually adheres to the window glass or glass fragments in the event of breakage. This is to say that if the glass becomes dislodged or is broken, the film holds the glass and/or glass particles, or at least most of the particles, in place.
In the usual application, a polyester material or film is applied to the glass and installed up to the surrounding gasket or frame. However, in Gross et al. U.S. Pat. No. 4,075,802 a film is disclosed as being adhesively secured to the plate glass, and a thin contoured strip is placed over the film edges and affixed to the window frame with wood screws. The disclosure appears to be particularly directed to residential applications having wood windows and relates to a rather primitive solution to the problem of securing the film perimeter to a window frame. However, Gross et al. do not disclose or suggest apparatus suitable for use in commercial settings wherein it is necessary that the securing system be not only functional but also aesthetically pleasing.